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Long cardio workout sessions can cause more harm than good, leading to the release of the stress hormone cortisol, which when produced excessively may contribute to a catabolic state, in which your tissues break down, as well as chronic disease

Too much cardio, such as marathon running, raises cardiac risk by seven-fold, and can lead to heart muscle scarring, and increased blood levels of cardiac enzymes, which are markers for heart injury

To get the most benefits of exercise you need to push your body hard enough for a challenge while allowing adequate time for recovery and repair to take place; one of the best ways to do this is to follow a fitness regimen that includes short bursts of high-intensity activities, which can be done using an elliptical machine, recumbent bike or even free weights

When you work out, it is wise to push as hard as you possibly can a few times a week, but you need to wisely gauge your body's tolerance to this stress, and give your body time to recuperate using rest and proper nutrition